Merge tag 'kvm-arm-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm updates for 5.3

- Add support for chained PMU counters in guests
- Improve SError handling
- Handle Neoverse N1 erratum #1349291
- Allow side-channel mitigation status to be migrated
- Standardise most AArch64 system register accesses to msr_s/mrs_s
- Fix host MPIDR corruption on 32bit

1 files changed, 6 insertions, 14 deletions

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 6c47f6ed3e94..3fc8d854d7fb 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -3110,6 +3110,12 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	log->log_transid = root->log_transid;
 	root->log_start_pid = 0;
 	/*
+	 * Update or create log root item under the root's log_mutex to prevent
+	 * races with concurrent log syncs that can lead to failure to update
+	 * log root item because it was not created yet.
+	 */
+	ret = update_log_root(trans, log);
+	/*
 	 * IO has been started, blocks of the log tree have WRITTEN flag set
 	 * in their headers. new modifications of the log will be written to
 	 * new positions. so it's safe to allow log writers to go in.
@@ -3128,8 +3134,6 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 
 	mutex_unlock(&log_root_tree->log_mutex);
 
-	ret = update_log_root(trans, log);
-
 	mutex_lock(&log_root_tree->log_mutex);
 	if (atomic_dec_and_test(&log_root_tree->log_writers)) {
 		/* atomic_dec_and_test implies a barrier */
@@ -5478,7 +5482,6 @@ static noinline int check_parent_dirs_for_sync(struct btrfs_trans_handle *trans,
 {
 	int ret = 0;
 	struct dentry *old_parent = NULL;
-	struct btrfs_inode *orig_inode = inode;
 
 	/*
 	 * for regular files, if its inode is already on disk, we don't
@@ -5498,16 +5501,6 @@ static noinline int check_parent_dirs_for_sync(struct btrfs_trans_handle *trans,
 	}
 
 	while (1) {
-		/*
-		 * If we are logging a directory then we start with our inode,
-		 * not our parent's inode, so we need to skip setting the
-		 * logged_trans so that further down in the log code we don't
-		 * think this inode has already been logged.
-		 */
-		if (inode != orig_inode)
-			inode->logged_trans = trans->transid;
-		smp_mb();
-
 		if (btrfs_must_commit_transaction(trans, inode)) {
 			ret = 1;
 			break;
@@ -6384,7 +6377,6 @@ void btrfs_record_unlink_dir(struct btrfs_trans_handle *trans,
 	 * if this directory was already logged any new
 	 * names for this file/dir will get recorded
 	 */
-	smp_mb();
 	if (dir->logged_trans == trans->transid)
 		return;